| US 7,557,761 B2 | ||
| Array antenna apparatus having at least two feeding elements and operable in multiple frequency bands | ||
| Hiroshi Iwai, Osaka (Japan); Atsushi Yamamoto, Kyoto (Japan); Tsutomu Sakata, Osaka (Japan); Toshiteru Hayashi, Kanagawa (Japan); and Kenichi Yamada, Kanagawa (Japan) | ||
| Assigned to Panasonic Corporation, Osaka (Japan) | ||
| Filed on Jan. 16, 2008, as Appl. No. 12/15,005. | ||
| Claims priority of application No. 2007-010162 (JP), filed on Jan. 19, 2007. | ||
| Prior Publication US 2008/0174508 A1, Jul. 24, 2008 | ||
| Int. Cl. H01Q 1/24 (2006.01) | ||
| U.S. Cl. 343—702 [343/853] | 13 Claims |
| 1. An array antenna apparatus comprising:
a first feeding element having a first feed point;
a second feeding element having a second feed point; and
a first parasitic element electrically connected to the respective first and second feeding elements, wherein
in a first frequency band, respective resonances in the first and second feeding elements substantially occur independent
of each other, by eliminating electromagnetic mutual coupling between the first and second feeding elements, and exciting
the first feeding element through the first feed point as well as exciting the second feeding element through the second feed
point, and
in a second frequency band lower than the first frequency band, a loop antenna having a certain electrical length is formed
by the first and second feeding elements and the first parasitic element, and a resonance of the loop antenna substantially
occurs by exciting the first feeding element through the first feed point.
|